In surface treating tools such as floor polishers, the surface treating member (e.g., floor pad) is typically rotated about an axis to polish or otherwise treat a surface such as a floor. The tool commonly includes a frame which has a rotatable support to which the pad is removably attached. In operation, the pad is mounted on the support wherein the support and pad are rotated at relatively high speeds about an axis as the tool is moved across the floor. The pad and its support are often adjustable so that the pad can be vertically lowered and raised relative to the floor to selectively increase and decrease the pad pressure on it. In more sophisticated models, such pad pressure on the floor is monitored and the pad automatically raised or lowered to maintain a desired pressure or range of pressures.
One problem that can and does often arise with such tools is that the operator may neglect to check to see that a pad is mounted on the tool before operating it. In this regard, the support for the pad is not intended to contact the floor as it will grind or otherwise damage it. Consequently, if the operator neglects to make sure a pad is present, the tool may end up lowering the padless support into engagement with the floor potentially resulting in significant damage to the floor as well as to the tool itself.
To prevent this, the present invention was developed. With it, the absence of a pad on the tool is automatically detected and the tool operated accordingly to prevent the padless support from being lowered into engagement with the floor.